/*
 * Copyright 2013-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.data.jpa.repository.query;

import com.bolt.support.sqlconfig.builder.SqlTemplateFactory;
import com.bolt.support.spring.jpa.query.JdbcQueryMethod;
import com.bolt.support.spring.jpa.query.NativeConfigQuery;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.QueryMethod;
import org.springframework.data.repository.query.QueryMethodEvaluationContextProvider;
import org.springframework.data.repository.query.RepositoryQuery;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.lang.Nullable;

import javax.persistence.EntityManager;

/**
 * Factory to create the appropriate {@link RepositoryQuery} for a {@link JpaQueryMethod}.
 *
 * @author Thomas Darimont
 * @author Mark Paluch
 */
enum JpaQueryFactory {

    INSTANCE;

    private static final SpelExpressionParser PARSER = new SpelExpressionParser();
    private static final Logger LOG = LoggerFactory.getLogger(JpaQueryFactory.class);

    /**
     * Creates a {@link RepositoryQuery} from the given {@link QueryMethod} that is potentially annotated with
     * {@link Query}.
     *
     * @param method                    must not be {@literal null}.
     * @param em                        must not be {@literal null}.
     * @param evaluationContextProvider
     * @return the {@link RepositoryQuery} derived from the annotation or {@code null} if no annotation found.
     */
    @Nullable
    AbstractJpaQuery fromQueryAnnotation(JpaQueryMethod method, EntityManager em,
                                         QueryMethodEvaluationContextProvider evaluationContextProvider) {

        LOG.debug("Looking up query for method {}", method.getName());
        return fromMethodWithQueryString(method, em, method.getAnnotatedQuery(), evaluationContextProvider);
    }

    /**
     * Creates a {@link RepositoryQuery} from the given {@link String} query.
     *
     * @param method                    must not be {@literal null}.
     * @param em                        must not be {@literal null}.
     * @param queryString               must not be {@literal null} or empty.
     * @param evaluationContextProvider
     * @return
     */
    @Nullable
    AbstractJpaQuery fromMethodWithQueryString(JpaQueryMethod method, EntityManager em, @Nullable String queryString,
                                               QueryMethodEvaluationContextProvider evaluationContextProvider) {

        if (queryString == null) {
            return null;
        }

        return method.isNativeQuery() ? new NativeJpaQuery(method, em, queryString, evaluationContextProvider, PARSER)
                : new SimpleJpaQuery(method, em, queryString, evaluationContextProvider, PARSER);
    }

    /**
     * Creates a {@link StoredProcedureJpaQuery} from the given {@link JpaQueryMethod} query.
     *
     * @param method must not be {@literal null}.
     * @param em     must not be {@literal null}.
     * @return
     */
    @Nullable
    public StoredProcedureJpaQuery fromProcedureAnnotation(JpaQueryMethod method, EntityManager em) {

        if (!method.isProcedureQuery()) {
            return null;
        }

        return new StoredProcedureJpaQuery(method, em);
    }

    public NativeConfigQuery fromNativeConfigQueryAnnotation(EntityManager em, JdbcQueryMethod method, SqlTemplateFactory sqlTemplateFactory) {
        if (!method.isNativeSQLConfigQuery()) {
            return null;
        }
        if (method.getAnnotatedSqlId() == null) {
            return null;
        }
        return new NativeConfigQuery(em, method, sqlTemplateFactory);
    }
}
